The largest beluga in the world. Beluga fish: significance and artificial breeding. Maturation and reproduction
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Hello everyone! Today we’ll talk about a fish like Beluga. This is not an ordinary fish. This fish is on the verge of extinction. Why fish because it reaches very large sizes in height and weight, and can also live about a hundred years. It can also be called a sad fish because of its appearance. Well, now let's talk about everything in order. Beluga is a member of the sturgeon family. He does not have a permanent place of residence and is therefore considered semi-passing. Spawns in rivers and lives in seas and rivers. Why can’t we call it completely marine or?
freshwater fish The fact is that large individuals
They switch to seafood cuisine only when there is not enough food for them in the rivers. Up to a certain size, it can live calmly in rivers and creeks, but when food begins to be scarce, it switches to marine inhabitants. The diet includes herring, gobies, sprat, in a word, a predator. In rivers they eat everything they can catch, from roach to crucian carp. The Black, Azov, and Caspian Seas are where the beluga lives. Which one is the most big beluga
was caught 
As for the size, the largest Beluga, according to unconfirmed data, weighed over two tons and was approximately nine meters long. If the information can be confirmed, then the beluga can easily be considered the largest freshwater fish on the planet. 
There is also accurate data on fish already caught. So in 1827, the weight of fish caught in the lower reaches of the Volga River was one and a half tons, 1500 kg. There in the Volga in 1922 the catch amounted to 75 pounds, which by our standards is about 1224 kg. The head weighed 146 kg, and the caviar was almost 259 kg. It’s not even possible to imagine, with a catch like this, the whole village can be provided with meat and still have some left over. Nowadays, such giants are practically not caught, although here is an example relatively not so long ago, but already in the last century, in 1970, a beluga weighing 1000 kg was caught; almost 100 kg of caviar was caught. Because of delicious meat and of great weight she was caught in industrial scale
. The average fishing weight is 50-70 kg.
Beluga is a long-living fish and can live 100 years. It can spawn many times, unlike its fellow Pacific salmon, which spawn only once in their entire lives and die after spawning. 
When fully ready to reproduce, these giants become almost like humans. Well, judge for yourself, males mature by 15-18 years, and females no earlier than 16-27 years. The average number of eggs scooped in is considered to be about 715 thousand eggs. The fertility of the beluga depends on the size of the female, as well as on the habitat. For the Volga beluga, this number ranges from 500 thousand to a million, and the Kurinsky ones of the same size produce 640 thousand eggs. It all depends on the habitat and living conditions.
The most expensive caviar is beluga
As for the caviar itself. Beluga eggs are quite large, 1.4-2.5 mm. The weight of the eggs is almost half the weight of the female. It has a pleasant delicate nutty flavor. 
The dark gray color, shiny hue, strong smell, all this made the caviar so tasty that on the black market in Russia, a buyer is ready to pay about 620 euros per kg for such a product without haggling. Abroad, beluga caviar can fetch approximately 7,000 euros. This price depends on the taste of this caviar and the fact that in Russia you officially cannot buy or sell beluga caviar anywhere. All transactions take place under a black flag.
Today in Russia there is a ban on beluga fishing, as it is on the verge of extinction. Beluga is also listed in the Red Book. It is quite a risky business to catch beluga. Because the deadlines are huge.
Taste qualities of beluga meat
Beluga meat, unlike other sturgeon breeds, is not fatty and has a very small percentage of fat content. But despite the fact that in tsarist times there were much more belugas than now, only tsars, princes and boyars could taste its delicious meat. As you can see, even then they understood meat, and considered beluga meat to be something unusual and wonderful. 
What secrets and beliefs is Beluga surrounded by?
But it was not only meat and caviar that beluga was valuable in those distant times. For example, almost every fisherman believed in the miraculous properties of beluga stone. With the help of this miracle stone you can heal people and entire villages. It was also believed that such an amulet brings happiness and a good catch to those who possess this stone. 
It was flat and oval in shape, and the size of a chicken egg. It could be obtained from the kidneys of large belugas. It could also be sold at a very high price or exchanged for something expensive. But these rumors were never confirmed. But as they say, such stones took place, most likely they were high-quality fakes of skilled craftsmen. There are still those who still believe in the miraculous properties of this stone, and in the fact that such a stone actually exists.
But the beluga's secrets don't end there.
Many fishermen were of the same opinion that the beluga is very poisonous fish. This belief also has not been confirmed. But the fishermen were sure that such fish could get rabies like a dog or cat. There was also an opinion that beluga liver is poisonous. But no matter what our ancestors believed, many are still inclined to believe that all these rumors were spread by the nobility. 
So that common people do not eat meat and do not catch beluga for use. It is possible that thanks to these rumors, in the past the beluga could grow up to 2 tons in weight and 9 meters in length.
Beluga fishermen deservedly call the king fish for its gigantic size.. Black and Caspian Sea- the permanent habitat of the beluga; it is found in the Adriatic and Mediterranean Seas. This fish is a long-liver, capable of living 100 years and laying eggs several times during its life. Beluga feeds on mollusks, crustaceans, and fish.This is a predator. Ducklings and baby seals were found in the stomachs of fish. Having reached sexual maturity, belugas go to freshwater rivers to spawn. It is believed that the spawning time of beluga occurs in May - June and lasts for a month. Eggs are deposited in deep-sea rivers with fast current and rocky bottom. Not finding a suitable place, the beluga will not spawn eggs, which will eventually dissolve inside the fish. To occupy a place for spring spawning, female belugas remain overwintering in rivers, hibernating and becoming overgrown with mucus. One female can carry up to 320 kg of caviar.
Pea-sized eggs, dark gray. Beluga caviar is eaten by other fish and carried away by the current. Out of 100,000 eggs, 1 survives. The juveniles, having spent a month at the spawning site, slide into the sea. Beluga caviar has great nutritional value. This was the reason that fish were caught in huge quantities, which led to a decrease in its numbers.
The sale of beluga caviar is currently prohibited by law.. After spawning, hungry belugas are busy searching for food. Old females even swallow inedible objects: driftwood, stones. They differ from young individuals by their large heads and emaciated bodies. Our ancestors did not eat such fish as food.
To catch a beluga, fishermen go out to sea, sailing 3 km from the shore. Using a pole, you need to find a place where there is a lot of shell rock at the bottom, which indicates the beluga’s feeding area. The bait is roach, asp, and herring. When dragging caught fish into the boat, you need to be careful, because there have been cases when huge fish the boat overturned and the fisherman found himself in the water. Beluga is listed in the Red Book and is an object of sport fishing. The caught trophy must be released.
At the beginning of the 20th century, beluga was a common game fish. Tons of this fish were caught in the Danube, Dnieper, and Volga. After the loss of natural spawning grounds, the number of beluga sturgeon decreased significantly.
No adults found, 98% are juveniles. A hybrid of beluga and sterlet - bester - is artificially grown.
There are stories that belugas weighing 1.5 tons and 2 tons were caught, but these facts have not been confirmed. In 1922, in the Caspian Sea there was the largest beluga in the world, weighing 1224 kg. A stuffed beluga 4.17 m long, caught in the early 20th century in the lower reaches of the Volga, is on display in the Kazan museum. When caught, the fish weighed 1000 kg. The Astrakhan museum houses a stuffed beluga caught in the Volga delta and weighing 966 kg.
All this allows us to call the beluga the largest freshwater fish. There are many facts known about the capture of belugas weighing 500, 800 kg. All of them date back to the late 19th and early 20th centuries. In our time average weight this fish weighs from 60 to 250 kg.
Hydroelectric power plants, sewage treatment plants, dams - all this interferes with the reproduction, growth and survival of fish.
We present to you a video of a large beluga caught in Atyrau.
Sturgeon and beluga in particular are considered very valuable commercial fish. However, due to a sharp decline in the number of natural populations in the second half of the 20th century, beluga fish is currently listed in the Red Book as rare view. However, it can be grown in artificial conditions, although with certain difficulties. Beluga caviar is the most expensive caviar in the world.
Beluga is an anadromous fish, that is, it lives in the seas, but rises to rivers to spawn. This species lives in the Caspian, Azov and Black Seas.
The most numerous is the Caspian population of beluga; it can be found everywhere in this sea. The main spawning site of the Caspian beluga is the Volga. Also, a small number of these fish go to spawn in the Ural, Kura and Terek rivers. A very insignificant number spawns in small rivers flowing into the Caspian Sea on the territory of Azerbaijan and Iran. But in general, it can be found in any river that is close enough to those places in the Caspian Sea where beluga fish are found.
In the past, spawning beluga entered rivers quite far - hundreds and even thousands of kilometers. For example, along the Volga it rose to Tver and even to the upper reaches of the Kama. However, due to the construction of numerous hydroelectric power stations on the rivers flowing into the Caspian Sea, modern belugas have to confine themselves only to the lower reaches.
Previously, the Azov beluga population was quite large, but today it is on the verge of extinction. From the Sea of Azov, fish rises to the Don and in very small quantities to the Kuban River. As in the case of the Caspian beluga, natural spawning grounds high upstream were cut off by the construction of a hydroelectric power station.
Finally, in the Black Sea, where the beluga fish lives, its population is also very small and concentrated mainly in the northwest of the sea, although cases of its appearance have been recorded off the coast of southern Crimea, the Caucasus and northern Turkey. For spawning, the local beluga is dressed in three largest rivers regions - Danube, Dnieper and Dniester. Some individuals spawn in the Southern Bug. Before the construction of a hydroelectric power station on the Dnieper, beluga was caught in the Kyiv area and even in Belarus. The situation is similar with the Dniester. But along the Danube it can still rise quite far - right up to the Serbian-Romanian border, where one of the two Danube hydroelectric power stations is located.
Until the 70s. In the last century, beluga was sometimes caught in the Adriatic Sea, where it went to spawn in the Po River. However, in the last few decades, not a single case of beluga being caught in this region has been recorded, which is why the Adriatic beluga is considered extinct.
Beluga - sturgeon fish; considered the largest of all freshwater fish. In historical chronicles there are references of questionable authenticity to the catching of individuals up to 9 meters long and weighing up to 2 tons. However, those sources that do not raise doubts provide no less impressive figures.
For example, a book on the state of Russian fisheries from 1861 mentions a beluga weighing 90 poods (one and a half tons), caught near Astrakhan in 1827. A reference book on freshwater fish in the USSR, published in 1948, mentions a female beluga weighing 75 pounds (more than 1,200 kg), which was caught in the Caspian Sea near the mouth of the Volga in 1922. Finally, everyone can see for themselves a stuffed one-color beluga displayed in National Museum Republic of Tatarstan in the city of Kazan.
The latest case of catching such massive individuals was recorded in 1989, when a beluga weighing 966 kg was caught in the Volga delta. Her stuffed animal can also be seen in one of the museums, but in Astrakhan.
According to experts, the largest beluga fish should be tens of years old. It is possible that some individuals could be 100 years or more old. However, these are all exceptional cases. The average weight of fish going to spawn in rivers is 90-120 kg for females and 60-90 kg for males. However, the beluga reaches even this size only at the age of 25-30 years. And immature young animals usually weigh no more than 20-30 kg.
If we leave alone the incredible size of this fish, then in general it has the typical sturgeon appearance. She has a massive, elongated, cylindrical body and a small, pointed nose. The beluga has a blunt, short snout and a large, crescent-shaped mouth. The mouth is bordered by a thick “lip”. The snout has wide, massive antennae.
The head and body are dotted with symmetrical rows of bony scutes (the so-called bugs): 12-13 on the back, 40-45 on the sides and 10-12 on the belly. The dominant color in the beluga is gray, which covers the back, sides and top of the head. The underside of the beluga is white.
The first thing mentioned in any description of beluga fish is its method of spawning. The main place of life of this fish is the sea, but it goes to spawning in big rivers, as has already been said earlier.
It is noteworthy that the beluga has so-called spring and winter forms (races). In particular, fish comes to the Volga in two waves: in the first half of autumn - winter, in the first half of spring - spring. However, this river is still dominated by the winter beluga, which spends the winter in river holes and then immediately begins spawning in April-May. In the Ural River, on the contrary, most belugas belong to the spring race; they spawn immediately after entering the river, and then swim back to the sea.
Like any sturgeon, beluga is a predatory fish. The young feed on all kinds of invertebrates and mollusks, catching them near the bottom in river mouths. After entering the open sea, the grown young animals quickly switch to feeding on fish. In the Caspian Sea, the basis of the beluga's diet is carp, roach, sprat, etc. In addition, the beluga does not hesitate to eat its own young and other representatives of the sturgeon family. The Black Sea beluga feeds mainly on anchovy and gobies.
Beluga reaches sexual maturity late: males at 12-14 years, females at 16-18 years. Due to such a long maturation under conditions of intensive industrial fishing, this species was on the verge of extinction.
As already mentioned, beluga spawning occurs in the second half of spring, although a significant part of the fish go to rivers in the fall. Beluga spawns when the spring flood reaches its peak and the river water temperature is 6-7°C. Caviar rushes on the rapids in deep places(at least 4 meters, more often 10-12 m) with a rocky bottom. One female lays at least 200 thousand eggs, but usually they count in the millions (up to 8 million). The eggs are quite large, about 4 mm in diameter.
Having finished spawning, beluga fish in the Volga and other rivers quickly go to sea. Young larvae also do not stay in the river.
Since ancient times it has been considered a commercial fish of high value. Active fishing has been going on since at least the 6th century BC. In the 20th century, with the development of industrial fishing methods, beluga fishing reached unprecedented proportions. For example, in the Volga alone in the 70s, 1.2-1.5 thousand tons of this fish were caught annually.
Unjustifiably intensive fishing of red beluga fish, as well as the construction of hydroelectric power stations everywhere in the rivers where it spawns, led to a sharp reduction in its numbers in the second half of the last century. Already in the early 90s, the catch dropped to 200-300 tons per year, and at the end of the decade - below 100 tons. In such conditions Russian authorities in 2000, industrial fishing of beluga sturgeon was banned on its territory, and a decade later other countries of the Caspian region joined the Russian Federation. Things are even worse in Cherny and Seas of Azov, where the beluga population has dropped to minuscule sizes.
The virtual impossibility of ensuring supplies to the consumer market of meat and, no less important, beluga caviar has created conditions for the development of fish farms specializing in this type of fish. Today they are the only legal suppliers of this type of product to store shelves. However, poaching, unfortunately, also occupies a significant share of this market.
In fish hatcheries, beluga is bred not only and not so much in its natural form, but rather hybridizes with other sturgeon - sterlet, stellate sturgeon and sturgeon. Bester, a fish resulting from crossing beluga and sterlet, has become especially widespread. It is not only grown in pond farms, but is even introduced into the Sea of Azov and freshwater reservoirs.
Beluga meat and especially its caviar are considered a true delicacy, from which you can prepare a real culinary masterpiece. This fish is subjected to all types of heat treatment: boiled, fried, baked, steamed and grilled. Beluga is also smoked, cut and canned. Beluga meat can be used to prepare the most Various types dishes including kebabs and salads.
With all this, beluga as a fish is very good for health. It has low calorie content and high content of easily digestible protein. Beluga contains many essential amino acids, which are urgently needed by our body, but are not synthesized in it, and can only be obtained from food. The meat of this fish contains a lot of calcium and phosphorus, which help restore and strengthen bones, as well as improve the condition of nails and hair. The potassium present in beluga improves the functioning of the heart muscle, and iron has a beneficial effect on the composition of the blood.
Beluga meat is rich in vitamin A, which affects visual acuity and skin condition. It also contains other important vitamins: B (important for muscles and nerve tissue), D (prevents the development of rickets and osteoporosis).
Separately, it is worth mentioning beluga caviar. Females lay large black eggs, which are incredibly highly prized by gourmets. Since industrial fishing of beluga is prohibited today, and in aquaculture it takes about 15 years to grow the fish to get caviar from it, the cost of this product reaches exorbitant prices. In Russia, 100 grams of beluga caviar costs about 10-20 thousand rubles, a kilogram - up to 150 thousand rubles. In Europe and other markets, the cost of a kilogram of this caviar ranges from 7-10 thousand dollars. Obviously, it is impossible to purchase such caviar in a regular store.
Beluga, as well as bester (a sturgeon fish hybrid of beluga and sterlet) can feed on artificial feed, and therefore are suitable for commercial fish farming. However, this technology is quite expensive, especially considering that to obtain caviar it is necessary to grow fish for at least 15 years.
Until the larvae reach a weight of 3 grams, they are grown in special trays. Nutrition is provided with both artificial and natural feed. After the larvae reach the specified weight, they are sent for rearing to ponds with a planting density of about 20 thousand specimens per hectare.
Further, the technology for breeding beluga fish at home provides for the transfer of fingerlings to feeding on minced fish of low-value breeds with various additives. At the same time, the young animals will provide themselves with a significant portion of their nutrition on their own from pond invertebrates. The predator instinct of beluga fingerlings appears at the end of summer, which implies an increase in the proportion of minced meat in its diet.
In beluga fingerlings, weight gain occurs most rapidly under conditions when the temperature and composition of the water are close to optimal values, therefore one of most important tasks It becomes the responsibility of the fish farmer to maintain these optimal conditions in the ponds.
In the first year, the average feed conversion of beluga is 2.8 units. At the end of the first season, the fish increases its weight from 3 to 150 g. With an average survival rate of fingerlings of 50%, their fish productivity reaches 20 c/ha.
Fingerlings are planted in wintering ponds (optimal reservoirs ranging from a quarter to half a hectare with a depth of 2-3 m, devoid of bottom silt and vegetation) in the amount of 120 thousand per hectare. Wintering begins in October - November and lasts until March. In winter, beluga is given food in the amount of 2% of the total mass of fish, and when surface ice Feeding is stopped altogether. It is natural for beluga underyearlings to lose 30-40% of their weight during this time. However, the size of the beluga fish does not change.
In the first ten days of April, the fish are sent back to the feeding ponds, where intensive feeding is immediately applied. Two-year-olds are given low-value fresh frozen fish. Young animals grow most actively in the second half of summer, and feed conversion increases during this period to 6 kg of feed per 1 kg of weight gain.
When two-year-olds reach a weight of 0.7 kg (by the end of the second season, about half of them are), they are sent for sale to the food chain. The remaining fish are left for another year and grown to a weight of 1.7-2 kg. In conditions of high survival rate of two-year-old and three-year-old fish (up to 95%), with strict adherence to cultivation technology, fish productivity will be 50-75 c/ha.
Beluga (lat. Huso huso) is a species of ray-finned fish of the order Sturgeon, family Sturgeon, genus Beluga.
Beluga is the oldest fish on the planet, appearing on earth over 200 million years ago. The only closest relative of the beluga is the kaluga, an inhabitant of the river basins of the Far Eastern region.
What does a beluga look like?
Beluga is considered the largest of all freshwater fish. The body of an adult reaches a length of 4.2 m, and the weight is about 1.5 tons, with females being slightly larger than males.
The beluga's thick, cylindrical body is covered with five rows of bone formations - scutes, and noticeably tapers towards the tail. The bone plates covering the head, sides and belly are poorly developed. More durable shields, 13 in number, are located on the back and perform a protective function.
Like all ray-finned fish, the fins of the beluga are distinguished by the presence of long and sharp, jagged rays: the dorsal contains at least 60 rays, the anal from 20 to 40.
The elongated head ends in an upturned, pointed nose, which is slightly translucent due to the absence of bony scutes. The beluga's mouth is quite wide, but does not extend beyond the sides of the head; a fleshy mouth hangs over it. upper lip. The antennae, located on the sides of the lower jaw, are wider and also longer than those of most sturgeons and perform an olfactory function.
The beluga's back is greenish or ash-gray in color, its belly is white or light gray, and its nose is characteristically yellow.
Where does the beluga live?
Belugas are migratory fish, and most They spend their lives in the waters of the Black, Azov and Caspian seas, and migrate to rivers only during the breeding season, and after spawning they go back to the sea.
By nature, belugas are solitary. Adults and mature individuals live at great depths; juveniles prefer shallow water, not far from the mouth of the river.
In summer, after spawning, the fish rests on average depth, and then fattens up before hibernation. Before the onset of cold weather, the body of the beluga is covered with a “fur coat” of a thick layer of mucus, and the fish falls into a state of suspended animation until spring.
What does beluga eat?
Large fish need a lot of food, and the size of individual individuals directly depends on the diet: the better the fish eats, the larger the size it reaches. Beluga's main food is different kinds fish, and the beluga begins to prey at a very young age, as a fry.
Adults successfully hunt both on the seabed and in the water column. The favorite foods of beluga are gobies, herring, sprat, sprat, anchovies, roach, anchovy, as well as representatives of the numerous carp family. A certain part of the diet consists of crustaceans and mollusks, and even small animals, for example, baby Caspian seals or waterfowl.
Beluga jumps out of the water. Beluga breeding
Belugas are long-lived animals, some specimens live up to 100 years, so they reach reproductive age late. Males are ready to breed at the age of 13-18 years, females mature at 16-27 years.
Spawning occurs in different time of the year and depending on this, beluga of the spring and autumn runs are distinguished.
Spring beluga enters rivers from late January until almost summer. The autumn beluga begins its migration at the end of summer and ends in December, so it is forced to winter at the bottom of the river in deep holes, and begins to reproduce only next spring.
Each sexually mature individual does not reproduce every year, but at a certain interval, usually 2-4 years. The spawning grounds of beluga pass along deep rocky ridges, amidst fast currents.
The fertility of a female depends on her size, but in any case, the amount of eggs spawned is 1/5 of her own body. The average amount of caviar is from 500 thousand to a million.
Dark gray eggs, 3 mm in diameter, look like peas. Thanks to its increased stickiness, caviar sticks perfectly to cold underwater rocks. At a water temperature of + 12-13 degrees, the incubation period is only 8 days.
Once born, the fry immediately switch to higher nutrition, bypassing the diet consisting of simple organisms. Without stopping, the juveniles go to the seas, where they live until the onset of puberty.
This is a fish of the sturgeon family, included in the Red Book as an endangered species. Lives in the Black, Caspian, Adriatic and Mediterranean seas. Because of gigantic size Beluga is the largest freshwater fish. Which is probably not surprising, since this species is unusually ancient. Sturgeons are more than 200 million years old, when very big fish and animals. Just look at the Danube Beluga - a relative of dinosaurs. So, What is the weight of the largest beluga on Earth?
In 1827, a beluga weighing one and a half tons, that is, 1,500 kilograms, was caught in the lower reaches of the Volga. Just imagine, this weight is comparable to the weight of some whales. Thus, a narwhal whale weighs about 940 kilograms, and a killer whale weighs 3,600 kilograms. That is, this fish weighed as much as half an orca and more than a narwhal!
On average, a standard beluga weighs about 19 kilograms(fish weight typical for the Northern Caspian). In the past, the average weight of beluga on the Volga was about 70-80 kg, in the Danube habitat of the Black Sea region - 50-60 kg, in the Sea of Azov the fish weighed 60-80 kg. But in the Don delta, males weighed 75-90 kg, and females - as much as 166 kilograms. Even the average weight already speaks of the enormous size and heaviness of this fish.
However, the average weight of most individuals in the population does not even come close to the record weight of the largest beluga. On May 11, 1922, at the mouth of the Volga, in the Caspian Sea, a beluga weighing 1224 kilograms, that is, 1.2 tons, was caught! At the same time, there were 667 kilograms on the body, 288 kilograms on the head and 146.5 kilograms on the calf.
The weight of the female during the spawning period increases many times. After all, beluga lays millions of eggs! In 1924, a female of the same weight of 1.2 tons was caught on the Biryucha Spit in the Caspian Sea. At the same time, 246 kilograms of weight were in the caviar. The total number of eggs was 7.7 million!
One female can carry up to 320 kilograms of caviar. Beluga carries them in itself until spring spawning. While waiting for him, the female spends the winter in the rivers, hibernating and becoming overgrown with mucus, like a stone. If it happens that the female does not find a suitable place for spawning, she will not spawn, and the eggs will eventually dissolve inside her.
It is not by chance that a huge amount of caviar is placed in the beluga by nature. Its task is to ensure the survival of the species. After all, beluga caviar is carried away by the current and eaten by other fish. Out of a hundred thousand eggs, only one will survive.
The records of giant belugas do not end with the above examples. On May 3, 1926, a 75-year-old female weighing more than one ton was caught at the mouth of the Urals. She carried 190 kg of caviar.
The Beluga, a stuffed animal of which is kept in the National Museum of Tatarstan, weighs about one ton. This fish was caught at the beginning of the 20th century in the lower reaches of the Volga. In the southern part of the Caspian Sea in 1836, a beluga weighing 960 kg was caught.
Over time, the record weight of the most large belugas It kept getting smaller and no longer exceeded a ton. In 1970, an 800-kilogram beluga was caught on the Volga, which contained 112 kg of caviar. There, in 1989, a fish weighing 966 kg was caught. Now it is kept in the Astrakhan Museum.